An art related to the fuel cell stack according to the present invention is disclosed in “FUEL CELL STACK STRUCTURE” of PTL 1.
In the fuel cell stack structure of PTL 1, multiple cell modules each formed by stacking multiple fuel cells are arranged in a row in a cell-stacking direction, and a space between adjacent ones of the cell modules is sealed with a bead gasket.
Further, the separator of each end cell of a cell module to be in contact with the bead gasket is given larger surface rigidity than the separators of center cells of the cell module. Specifically, in order for the separator of the end cell to have the larger surface rigidity than those of the center cells, a flat panel is superimposed on the separator of the end cell.